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1.
Molecules ; 28(18)2023 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-37764293

RESUMO

Secreted phospholipases A2 are snake-venom proteins with many biological activities, notably anti-tumor activity. Phospholipases from the same snake type but different geographical locations have shown similar biochemical and biological activities with minor differences in protein sequences. Thus, the discovery of a new phospholipase A2 with unique characteristics identified in a previously studied venom could suggest the origins of these differences. Here, a new Group II secreted phospholipase A2 (Cc-PLA2-II) from the snake venom of Saudi Cerastes cerastes gasperetti was isolated and characterized. The purified enzyme had a molecular weight of 13.945 kDa and showed high specific activity on emulsified phosphatidylcholine of 1560 U/mg at pH 9.5 and 50 °C with strict calcium dependence. Interestingly, stability in extreme pH and high temperatures was observed after enzyme incubation at several pH levels and temperatures. Moreover, a significant dose-dependent cytotoxic anti-tumor effect against six human cancer cell lines was observed with concentrations of Cc-PLA2 ranging from 2.5 to 8 µM. No cytotoxic effect on normal human umbilical-vein endothelial cells was noted. These results suggest that Cc-PLA2-II potentially has angiogenic activity of besides cytotoxicity as part of its anti-tumor mechanism. This study justifies the inclusion of this enzyme in many applications for anticancer drug development.


Assuntos
Antineoplásicos , Viperidae , Animais , Humanos , Fosfolipases A2 do Grupo II , Arábia Saudita , Fosfolipases A2/farmacologia , Fosfolipases A2/química , Fosfolipases , Venenos de Víboras/farmacologia , Venenos de Víboras/química , Antineoplásicos/farmacologia
2.
Molecules ; 27(11)2022 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-35684381

RESUMO

Secretory group V phospholipase A2 (PLA2-V) is known to be involved in inflammatory processes in cellular studies, nevertheless, the biochemical and the enzymatic characteristics of this important enzyme have been unclear yet. We reported, as a first step towards understanding the biochemical properties, catalytic characteristics, antimicrobial and cytotoxic effects of this PLA2, the production of PLA2-V from dromedary. The obtained DrPLA2-V has an absolute requirement for Ca2+ and NaTDC for enzymatic activity with an optimum pH of 9 and temperature of 45 °C with phosphatidylethanolamine as a substrate. Kinetic parameters showed that Kcat/Kmapp is 2.6 ± 0.02 mM-1 s-1. The enzyme was found to display potent Gram-positive bactericidal activity (with IC50 values of about 5 µg/mL) and antifungal activity (with IC50 values of about 25 µg/mL)in vitro. However, the purified enzyme did not display a cytotoxic effect against cancer cells.


Assuntos
Antibacterianos , Camelus , Animais , Antibacterianos/farmacologia , Cinética , Fosfolipases A2/farmacologia , Temperatura
3.
Molecules ; 27(13)2022 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-35807466

RESUMO

The main objective of the current study was the extraction, purification, and enzymatic characterization of a potent proteinaceous amylase inhibitor from Moringa oleifera. The antimicrobial potential and insecticide effects against C. maculates insect larvae were also studied. The α-amylase inhibitor was extracted in methanol (with an inhibitory activity of 65.6% ± 4.93). Afterwards, the inhibitor αAI.Mol was purified after a heat treatment at 70 °C for 15 min followed by one chromatographic step of Sephadex G-50. An apparent molecular weight of 25 kDa was analyzed, and the N-terminal sequence showed the highest identity level (89%) with the monomeric α-amylase inhibitor from Triticum dicoccoides. αAI.Mol was found to tolerate pH values ranging from 5.0 to 11.0 and showed maximal activity at pH 9.0. Thermal stability was remarkably important, since the inhibitory activity was maintained at 55% after 1 h of incubation at 70 °C and at 53% after an incubation of 45 min at 80 °C. The potency of the current purified inhibitor against amylases from different origins indicates that αAI.Mol seems to possess the highest affinity toward human salivary α-amylase (90% inhibitory activity), followed by the α-amylase of insects Callosobruchus maculatus and Tribolium confusum (71% and 61%, respectively). The kinetic parameters were also calculated, and the Kmax and Vmax of the digestive amylase were estimated at 185 (mmol/min/mg) and 0.13 mM, respectively. The inhibitor possesses a strong bactericidal effect against Gram+ and Gram- strains, and the MIC values were >1 against B. cereus but >6 against E. coli. Interestingly, the rates of survival and pupation of C. maculates insect larvae were remarkably affected by the purified αAI.Mol from Moringa oleifera.


Assuntos
Besouros , Inseticidas , Moringa oleifera , Amilases , Animais , Escherichia coli , Humanos , Insetos , Inseticidas/química , Inseticidas/farmacologia , Larva , Extratos Vegetais/farmacologia , alfa-Amilases
4.
Molecules ; 27(24)2022 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-36557867

RESUMO

Biodiesel is one of the important biofuels as an alternative to petroleum-based diesel fuels. In the current study, enzymatic transesterification reaction was carried out for the production of biodiesel from waste cooking oil (WCO) and experimental conditions were optimized, in order to reach maximum biodiesel yield. Bacillus stearothermophilus and Staphylococcus aureus lipase enzymes were individually immobilized on CaCO3 to be used as environmentally friendly catalysts for biodiesel production. The immobilized lipases exhibited better stability than free ones and were almost fully active after 60 days of storage at 4 °C. A significant biodiesel yield of 97.66 ± 0.57% was achieved without any pre-treatment and at 1:6 oil/methanol molar ratio, 1% of the enzyme mixture (a 1:1 ratio mixture of both lipase), 1% water content, after 24 h at 55 °C reaction temperature. The biocatalysts retained 93% of their initial activities after six cycles. The fuel and chemical properties such as the cloud point, viscosity at 40 °C and density at 15 °C of the produced biodiesel complied with international specifications (EN 14214) and, therefore, were comparable to those of other diesels/biodiesels. Interestingly, the resulting biodiesel revealed a linolenic methyl ester content of 0.55 ± 0.02% and an ester content of 97.7 ± 0.21% which is in good agreement with EN14214 requirements. Overall, using mixed CaCO3-immobilized lipases to obtain an environmentally friendly biodiesel from WCO is a promising and effective alternative for biodiesel production catalysis.


Assuntos
Biocombustíveis , Ésteres , Biocombustíveis/análise , Esterificação , Lipase/química , Enzimas Imobilizadas/metabolismo , Culinária , Óleos de Plantas
5.
Molecules ; 27(16)2022 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-36014408

RESUMO

In this study, we will present an efficient and selective adsorbent for the removal of Cu(II) ions from aqueous solutions. The silica-based adsorbent is functionalized by 2-phenylimidazo[1,2-a] pyridine-3-carbaldehyde (SiN-imd-py) and the characterization was carried out by applying various techniques including FT-IR, SEM, TGA and elemental analysis. The SiN-imd-py adsorbent shows a good selectivity and high adsorption capacity towards Cu(II) and reached 100 mg/g at pH = 6 and T = 25 °C. This adsorption capacity is important compared to other similar adsorbents which are currently published. The adsorption mechanism, thermodynamics, reusability and the effect of different experimental conditions, such as contact time, pH and temperature, on the adsorption process, were also investigated. In addition, a theoretical study was carried out to understand the adsorption mechanism and the active sites of the adsorbent, as well as the stability of the complex formed and the nature of the bonds.


Assuntos
Dióxido de Silício , Poluentes Químicos da Água , Adsorção , Concentração de Íons de Hidrogênio , Cinética , Modelos Teóricos , Piridinas , Dióxido de Silício/química , Soluções , Espectroscopia de Infravermelho com Transformada de Fourier , Água/química , Poluentes Químicos da Água/química
6.
Molecules ; 26(4)2021 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-33672726

RESUMO

This study was conducted to identify a new alkaline and thermophilic protease (Ba.St.Pr) produced from Bacillus stearothermophilus isolated from olive oil mill sols and to evaluate its culture conditions, including temperature, pH, carbon and nitrogen sources, and incubation time. The optimum culture conditions for cell growth (10 g/L) and protease production (5050 U/mL) were as follows: temperature 55 °C, pH 10, inoculation density 8 × 108 CFU/mL, and incubation time 24 h. The use of 3% yeast extract as the nitrogen sources and galactose (7.5 g/L) as the carbon sources enhanced both cell growth and protease production. Using reversed-phase analytical HPLC on C-8 column, the new protease was purified with a molecular mass of approximately 28 kDa. The N-terminal sequence of Ba.St.Pr exhibited a high level of identity of approximately 95% with those of Bacillus strains. Characterization under extreme conditions revealed a novel thermostable and alkaline protease with a half-life time of 187 min when incubated with combined Ca2+/mannitol. Ba.St.Pr demonstrated a higher stability in the presence of surfactant, solvent, and Ca2+ ions. Consequently, all the evaluated activity parameters highlighted the promising properties of this bacterium for industrial and biotechnological applications.


Assuntos
Bacillus/enzimologia , Proteínas de Bactérias/química , Biotecnologia , Endopeptidases/química , Azeite de Oliva/metabolismo , Temperatura , Proteínas de Bactérias/biossíntese , Proteínas de Bactérias/isolamento & purificação , Carbono/química , Carbono/metabolismo , Endopeptidases/biossíntese , Endopeptidases/isolamento & purificação , Concentração de Íons de Hidrogênio , Nitrogênio/química , Nitrogênio/metabolismo , Azeite de Oliva/química
7.
Molecules ; 26(11)2021 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-34071141

RESUMO

The pathogenesis of colorectal cancer is a multifactorial process. Dysbiosis and the overexpression of COX-2 and LDHA are important effectors in the initiation and development of the disease through chromosomal instability, PGE2 biosynthesis, and induction of the Warburg effect, respectively. Herein, we report the in vitro testing of some new quinoxalinone and quinazolinone Schiff's bases as: antibacterial, COX-2 and LDHA inhibitors, and anticolorectal agents on HCT-116 and LoVo cells. Moreover, molecular docking and SAR analyses were performed to identify the structural features contributing to the biological activities. Among the synthesized molecules, the most active cytotoxic agent, (6d) was also a COX-2 inhibitor. In silico ADMET studies predicted that (6d) would have high Caco-2 permeability, and %HIA (99.58%), with low BBB permeability, zero hepatotoxicity, and zero risk of sudden cardiac arrest, or mutagenicity. Further, (6d) is not a potential P-gp substrate, instead, it is a possible P-gpI and II inhibitor, therefore, it can prevent or reverse the multidrug resistance of the anticancer drugs. Collectively, (6d) can be considered as a promising lead suitable for further optimization to develop anti-CRC agents or glycoproteins inhibitors.


Assuntos
Neoplasias Colorretais/tratamento farmacológico , Quinazolinonas/farmacologia , Quinoxalinas/farmacologia , Antibacterianos/farmacologia , Antineoplásicos/farmacologia , Células CACO-2 , Proliferação de Células/efeitos dos fármacos , Neoplasias Colorretais/metabolismo , Inibidores de Ciclo-Oxigenase 2/farmacologia , Desenho de Fármacos , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Humanos , L-Lactato Desidrogenase/antagonistas & inibidores , Simulação de Acoplamento Molecular , Estrutura Molecular , Relação Estrutura-Atividade
8.
Metab Brain Dis ; 35(1): 215-224, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31625070

RESUMO

The current study evaluated the protective and therapeutic potency of bee pollen in ameliorating the toxic effects of methylmercury (MeHg), by measuring certain biochemical parameters related to neurotransmission, neuroinflammation, apoptosis, and glutamate excitotoxicity in the male neonate brain. Healthy, pregnant female rats (N = 40) were randomly divided into 5 groups, each comprising10 male neonates, as follows: (i) neonates delivered by control mothers; (ii) neonates delivered by MeHg-treated mothers who received 0.5 mg/kg BW/day MeHg via drinking water from gestational day 7 till postnatal day 7; (iii) neonates delivered by bee pollen treated mothers who received 200-mg/kg BW bee pollen from postnatal day 0 for 4 weeks; (iv) protective group of neonates delivered by MeHg and bee pollen-treated mothers, who continued to receive bee pollen until day 21 at the same dose, and (v) therapeutic group of neonates delivered by MeHg- treated mothers followed by bee pollen treatment, wherein they received 200-mg/kg BW bee pollen from postnatal day 0 for 4 weeks. Selected biochemical parameters in brain homogenates from each group were measured. MeHg-treated groups exhibited various signs of brain toxicity, such as a marked reduction in neurotransmitters (serotonin (5-HT), nor-adrenalin (NA), dopamine (DA)) and gamma aminobutyric acid (GABA) and elevated levels of interferon gamma (IFN-γ), caspase-3, and glutamate (Glu). Bee pollen effectively reduced the neurotoxic effects of MeHg. Minimal changes in all measured parameters were observed in MeHg-treated animals compared to the control group. Therefore, bee pollen may safely improve neurotransmitter defects, inflammation, apoptosis, and glutamate excitotoxicity.


Assuntos
Abelhas , Compostos de Metilmercúrio/toxicidade , Fármacos Neuroprotetores/uso terapêutico , Síndromes Neurotóxicas/prevenção & controle , Pólen , Efeitos Tardios da Exposição Pré-Natal/prevenção & controle , Animais , Animais Recém-Nascidos , Feminino , Masculino , Síndromes Neurotóxicas/metabolismo , Gravidez , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Distribuição Aleatória , Ratos , Ratos Wistar
9.
Molecules ; 25(22)2020 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-33233753

RESUMO

The main objective of the current study was the extraction, purification, and biochemical characterization of a protein protease inhibitor from Conyzadioscoridis. Antimicrobial potential and cytotoxic effects were also examined. The protease inhibitor was extracted in 0.1 M phosphate buffer (pH 6-7). Then, the protease inhibitor, named PDInhibitor, was purified using ammonium sulfate precipitation followed by filtration through a Sephadex G-50 column and had an apparent molecular weight of 25 kDa. The N-terminal sequence of PDInhibitor showed a high level of identity with those of the Kunitz family. PDInhibitor was found to be active at pH values ranging from 5.0 to 11.0, with maximal activity at pH 9.0. It was also fully active at 50 °C and maintained 90% of its stability at over 55 °C. The thermostability of the PDInhibitor was clearly enhanced by CaCl2 and sorbitol, whereas the presence of Ca2+ and Zn2+ ions, Sodium taurodeoxycholate (NaTDC), Sodium dodecyl sulfate (SDS), Dithiothreitol (DTT), and ß-ME dramatically improved the inhibitory activity. A remarkable affinity of the protease inhibitor with available important therapeutic proteases (elastase and trypsin) was observed. PDInhibitor also acted as a potent inhibitor of commercial proteases from Aspergillus oryzae and of Proteinase K. The inhibitor displayed potent antimicrobial activity against gram+ and gram- bacteria and against fungal strains. Interestingly, PDInhibitor affected several human cancer cell lines, namely HCT-116, MDA-MB-231, and Lovo. Thus, it can be considered a potentially powerful therapeutic agent.


Assuntos
Anti-Infecciosos/química , Anti-Infecciosos/isolamento & purificação , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Conyza/química , Inibidores de Proteases/química , Inibidores de Proteases/isolamento & purificação , Anti-Infecciosos/farmacologia , Antineoplásicos/farmacologia , Cromatografia em Gel , Estabilidade de Medicamentos , Eletroforese em Gel de Poliacrilamida , Humanos , Concentração de Íons de Hidrogênio , Testes de Sensibilidade Microbiana , Oxidantes/química , Oxidantes/farmacologia , Oxirredução/efeitos dos fármacos , Inibidores de Proteases/farmacologia , Solventes/química , Temperatura
10.
J Enzyme Inhib Med Chem ; 34(1): 672-683, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30821525

RESUMO

Some new 3H-quinazolin-4-one derivatives were synthesised and screened for anticancer, antiphospholipases, antiproteases, and antimetabolic syndrome activities. Compound 15d was more potent in reducing the cell viabilities of HT-29 and SW620 cells lines to 38%, 36.7%, compared to 5-FU which demonstrated cell viabilities of 65.9 and 42.7% respectively. The IC50 values of 15d were ∼20 µg/ml. Assessment of apoptotic activity revealed that 15d decreased the cell viability by down regulating Bcl2 and BclxL. Moreover, compounds, 8j, 8d/15a/15e, 5b, and 8f displayed lowered IC50 values than oleanolic acid against proinflammatory isoforms of hGV, hG-X, NmPLA2, and AmPLA2. In addition, 8d, 8h, 8j, 15a, 15b, 15e, and 15f showed better anti-α-amylase than quercetin, whereas 8g, 8h, and 8i showed higher anti-α-glucosidase activity than allopurinol. Thus, these compounds can be considered as potential antidiabetic agents. Finally, none of the compounds showed higher antiproteases or xanthine oxidase activities than the used reference drugs.


Assuntos
Antineoplásicos/farmacologia , Inibidores Enzimáticos/farmacologia , Síndrome Metabólica/tratamento farmacológico , Peptídeo Hidrolases/metabolismo , Fosfolipases/antagonistas & inibidores , Quinazolinonas/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Células HT29 , Humanos , Síndrome Metabólica/metabolismo , Estrutura Molecular , Fosfolipases/metabolismo , Quinazolinonas/síntese química , Quinazolinonas/química , Relação Estrutura-Atividade , Células Tumorais Cultivadas
11.
Cell Mol Biol (Noisy-le-grand) ; 64(13): 55-62, 2018 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-30403596

RESUMO

Many enzymes are involved in numerous pathologies which are related to metabolic reactions and inflammatory diseases such as pancreatic lipase, α-amylase, α-glucosidase and xanthine oxidase and secreted phospholipases A2 (Group IIA, V and X), respectively. Therefore, inhibiting these enzymes offer the potential to block production of more inflammatory substances and decrease the risk factors for cardiovascular diseases. The purpose of this study was to investigate some potent, bioavailable and selective inhibitors of some catalytic proteins implicated to metabolic syndrome and their antioxidant effects from various solvent extracts of R. frangula leaves. The anti-inflammatory, obesity, diabete and XO potentials were evaluated through analyses of inhibition activities of corresponding metabolites.The water extract exhibited an important inhibitory effect on human, dromedary and stingray sPLA2-G IIA achieved an IC50 of 0.16±0.06, 0.19±0.05 and 0.07±0.01 mg/mL, respectively. Likewise, the same fraction demonstrated the highest pancreatic lipase inhibitory activity using two different substrates. Indeed, 50% of dromedary pancreatic lipase inhibition was demonstrated for 5 min and 15 min using olive oil and TC4 substrates, respectively. Besides, it was established that methanolic extract had more effective inhibitory lipase activity than ORLISTAT used as a specific inhibitor of gastric, pancreatic and carboxyl ester lipase for treating obesity, with an IC50 of 5.51±0.27 and 91.46±2.3 µg/mL, respectively. In the case of α-amylase, α-glucosidase and xanthine oxidase, the crude methanolic extract showed a potential inhibitory effect with an IC50 of 45±3.45, 3±0.15 and 27±1.71 µg/mL, respectively. Conclusively, R. frangula leaves extracts showed a potential value of some sPLA2, some metabolic enzymes and XO inhibitors as anti-inflammatory and metabolic syndrome drugs.


Assuntos
Inibidores Enzimáticos/farmacologia , Enzimas/metabolismo , Inflamação/enzimologia , Extratos Vegetais/farmacologia , Folhas de Planta/química , Rhamnus/química , Animais , Humanos , Concentração Inibidora 50 , Metanol/química , Solventes , Ácido Taurodesoxicólico/farmacologia
12.
Cell Mol Biol (Noisy-le-grand) ; 64(1): 103-106, 2018 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-29412802

RESUMO

The gut and the liver are closely linked to each other, as changes in the gut microbiota can play a significant role in the development of many liver diseases. Gut bacteria respond rapidly to changes in diet and thus can affect the liver through their metabolites. The impact of a high lipid diet on the liver in the presence of an altered gut flora modulated by ampicillin was investigated. The study was performed on 30 male Western albino rats randomly divided into 3 groups: control (phosphate buffered saline treated), group II (ampicillin 50 mg/kg for three weeks to induce microbiota alterations and fed on standard diet) and group III (same dose of ampicillin and fed on a lipid rich diet). Stool samples were collected for qualitative determination of bacteria. Serum hepato-specific markers, in addition to Glutathione (GSH), Lipid peroxidase (MDA), Glutathione-S- transferase(GST), and vitamin C in liver tissues, were measured. Altered gut microbiota significantly increased the level of the hepato-specific marker MDA and reduced the GST, GSH and vitamin C levels. However, animals fed a lipid rich diet displayed a more significant shift in hepatic markers and antioxidants. Moreover, a new switch in composition of the gut bacteria was observed by feeding the lipid rich diet. Our study showed that bacterial overgrowth in the gut can be associated with liver dysfunction and that a high lipid diet can promote the overgrowth of some liver damaging microflora during antibiotic treatment.


Assuntos
Dieta Hiperlipídica , Microbioma Gastrointestinal , Fígado/metabolismo , Ampicilina/farmacologia , Animais , Antibacterianos/farmacologia , Ácido Ascórbico/metabolismo , Glutationa/metabolismo , Glutationa Transferase/metabolismo , Fígado/enzimologia , Masculino , Peroxidases/metabolismo , Ratos
13.
J Enzyme Inhib Med Chem ; 32(1): 1143-1151, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28856929

RESUMO

Elevated blood glucose and increased activities of secreted phospholipase A2 (sPLA2) are strongly linked to coronary heart disease. In this report, our goal was to develop small heterocyclic compound that inhibit sPLA2. The title compounds were also tested against α-glucosidase and α-amylase. This array of enzymes was selected due to their implication in blood glucose regulation and diabetic cardiovascular complications. Therefore, two distinct series of quinoxalinone derivatives were synthesised; 3-[N'-(substituted-benzylidene)-hydrazino]-1H-quinoxalin-2-ones 3a-f and 1-(substituted-phenyl)-5H-[1,2,4]triazolo[4,3-a]quinoxalin-4-ones 4a-f. Four compounds showed promising enzyme inhibitory effect, compounds 3f and 4b-d potently inhibited the catalytic activities of all of the studied proinflammatory sPLA2. Compound 3e inhibited α-glucosidase (IC50 = 9.99 ± 0.18 µM); which is comparable to quercetin (IC50 = 9.93 ± 0.66 µM), a known inhibitor of this enzyme. Unfortunately, all compounds showed weak activity against α-amylase (IC50 > 200 µM). Structure-based molecular modelling tools were utilised to rationalise the SAR compared to co-crystal structures with sPLA2-GX as well as α-glucosidase. This report introduces novel compounds with dual activities on biochemically unrelated enzymes mutually involved in diabetes and its complications.


Assuntos
Inibidores Enzimáticos/farmacologia , Fosfolipases A2 Secretórias/antagonistas & inibidores , Quinoxalinas/farmacologia , alfa-Glucosidases/metabolismo , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Humanos , Modelos Moleculares , Estrutura Molecular , Fosfolipases A2 Secretórias/metabolismo , Quinoxalinas/síntese química , Quinoxalinas/química , Relação Estrutura-Atividade
14.
Biotechnol Appl Biochem ; 63(3): 378-90, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-25828848

RESUMO

In this study, a new strain, ALA1, was identified as Staphylococcus aureus by biochemical tests, and its 16S ribosomal DNA sequence was isolated from dromedary milk. ALA1 lipase production was optimized in shake flask experiments and measured with varying pH (3-11), temperature (20-55 °C) and substrate concentrations. The maximum lipase production was recorded at pH 8 and 30 °C for up to 30 H of culture period for the S. aureus ALA1 strain. Among the substrates tested, selected carbon sources, xylose, nitrogen source, yeast extract, and olive oil (1%) were suitable for maximizing lipase production. The effects of surfactants were investigated and showed that Tween 20, Tween 80, and Triton X-100 prevented lipase production. Interestingly, isolate ALA1 was able to grow in high concentrations of benzene or toluene (up to 50% (v/v)). Moreover, the lipolytic activity of the S. aureus ALA1 lipase was stimulated by diethyl ether, whereas almost 100% of S. aureus ALA1 lipase activity was retained in 25% acetone, acetonitrile, benzene, 2-propanol, ethanol, methanol, or toluene. Because of its stability in organic solvent, the S. aureus ALA1 lipase was used as a biocatalyst to synthesize high levels of added value molecules. S. aureus ALA1 lipase could be considered as an ideal choice for applications in detergent formulations because of its high stability and compatibility with various surfactants, oxidizing agents, and commercial detergents.


Assuntos
Biocatálise , Indústrias , Lipase/química , Lipase/metabolismo , Compostos Orgânicos/farmacologia , Solventes/farmacologia , Staphylococcus aureus/enzimologia , Staphylococcus aureus/isolamento & purificação , Detergentes/farmacologia , Estabilidade Enzimática/efeitos dos fármacos , Esterificação , Lipólise , Oxidantes/farmacologia , Tensoativos/farmacologia
15.
Molecules ; 21(12)2016 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-27918459

RESUMO

Some novel hydrazone derivatives 6a-o were synthesized from the key intermediate 4-Chloro-N-(2-hydrazinocarbonyl-phenyl)-benzamide 5 and characterized using IR, ¹H-NMR, 13C-NMR, mass spectroscopy and elemental analysis. The inhibitory potential against two secretory phospholipase A2 (sPLA2), three protease enzymes and eleven bacterial strains were evaluated. The results revealed that all compounds showed preferential inhibition towards hGIIA isoform of sPLA2 rather than DrG-IB with compounds 6l and 6e being the most active. The tested compounds exhibited excellent antiprotease activity against proteinase K and protease from Bacillus sp. with compound 6l being the most active against both enzymes. Furthermore, the maximum zones of inhibition against bacterial growth were exhibited by compounds; 6a, 6m, and 6o against P. aeruginosa; 6a, 6b, 6d, 6f, 6l, 6m, 6n, and 6o against Serratia; 6k against S. mutans; and compounds 6a, 6d, 6e, 6m, and 6n against E. feacalis. The docking simulations of hydrazones 6a-o with GIIA sPLA2, proteinase K and hydrazones 6a-e with glutamine-fructose-6-phosphate transaminase were performed to obtain information regarding the mechanism of action.


Assuntos
Antibacterianos/farmacologia , Endopeptidase K/antagonistas & inibidores , Hidrazonas/síntese química , Hidrazonas/farmacologia , Inibidores de Fosfolipase A2/farmacologia , Inibidores de Proteases/farmacologia , Antibacterianos/síntese química , Bacillus/crescimento & desenvolvimento , Benzamidas/química , Enterococcus faecalis/crescimento & desenvolvimento , Simulação de Acoplamento Molecular , Inibidores de Fosfolipase A2/síntese química , Inibidores de Proteases/síntese química , Espectroscopia de Prótons por Ressonância Magnética , Pseudomonas aeruginosa/crescimento & desenvolvimento , Serratia/crescimento & desenvolvimento , Streptococcus mutans/crescimento & desenvolvimento , Relação Estrutura-Atividade
16.
Indian J Biochem Biophys ; 52(2): 179-88, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26118130

RESUMO

Lipases are the enzymes of choice for laundry detergent industries, owing to their triglyceride removing ability from the soiled fabric, which eventually reduces the usage of phosphate-based chemical cleansers in the detergent formulation. In this study, a novel thermo-alkaline lipase-producing strain identified as Bacillus stearothermophilus was isolated from the soil samples of olive oil mill. Enhanced lipase production was observed at 55 degrees C, pH 11 and after 48 h of incubation. Among the substrates tested, xylose (a carbon source), peptone (a nitrogen source) and olive oil at a concentration of 1% were suitable substrates for enhancing lipase production. MgSO4 and Tween-80 were suitable substrates for maximizing lipase production. The enzyme was purified to homogeneity by a single CM-Sephadex column chromatography and revealed molecular mass of 67 kDa. The enzyme (BL1) was active over a wide range of pH from 9.0 to 13.0, with an optimum at pH 11.0, exhibited maximal activity at 55 degreesC and retained more than 70% of its activity after incubation at 70 degrees C or pH 13 for 0.5 h or 24 h, respectively. The enzyme hydrolyzed both short and long-chain triacylglycerols at comparable rates. BL1 was studied in a preliminary evaluation for use in detergent formulation solutions. This novel lipase showed extreme stability towards non-ionic and anionic surfactants after pre-incubation for 1 h at 40 degrees C, and good stability towards oxidizing agents. Additionally, the enzyme showed excellent stability and compatibility with various commercial detergents, suggesting its potential as an additive in detergent formulations.


Assuntos
Álcalis/metabolismo , Detergentes/metabolismo , Geobacillus stearothermophilus/enzimologia , Lipase/metabolismo , Estabilidade Enzimática
17.
ACS Omega ; 9(11): 13332-13341, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38524442

RESUMO

A novel protease inhibitor isolated from date palm Phoenix dactylifera(L.) flowers (PIDF) was purified and characterized. A heat and acidic treatment step followed by ethanol precipitation and reverse-phase high-performance chromatography was applied to purify this natural protease inhibitor to homogeneity with a single band of about 19 kDa. The stability study depicted that PIDF was fully stable at 40 °C and retained 65% of its initial activity after heating at 50 °C for 24 h. Its thermal stability at 70 °C was markedly enhanced by adding calcium, bovine serum albumin, and sorbitol as well as by metal divalent cations, especially Mg2+ and Hg2+. This protease inhibitor showed high inhibitory activity against therapeutic proteases, including pepsin, trypsin, chymotrypsin, and collagenase, and acted as a potent inhibitor of some commercial microbial proteases from Aspergillus oryzae, Bacillus. sp, and Bacillus licheniformis. Moreover, a potent antibacterial spectrum against Gram (+) and Gram (-) bacterial strains and an efficient antifungal effect were observed. Its cytotoxicity toward human colorectal cancer cell LoVo and HCT-116 lines suggested that PIDF could serve as a new therapeutic target inhibiting human colorectal cancer.

18.
Front Mol Biosci ; 11: 1365440, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38469182

RESUMO

Introduction: Cadmium (Cd) is a harmful heavy metal that results in many toxic issues. Urtica pilulifera showed potential pharmaceutical applications. This study investigated the possible ameliorative mechanism of Urtica pilulifera leaves extract (UPLE) against hepatotoxicity induced by cadmium chloride (CdCl2) in mice. Methods: In vitro phytochemical screening and the metal-chelating activity of UPLE were ascertained. Four groups of forty male mice were used (n = 10) as follows; Group 1 (G1) was a negative control. G2 was injected i.p., with UPLE (100 mg/kg b. wt) daily. G3 was injected i.p., with Cd (5 mg/kg b. wt) daily. G4 was injected with Cd as in G3 and with UPLE as in G2. On day 11, the body weight changes were evaluated, blood, and serum samples were collected for hematological and biochemical assessments. Liver tissues were used for biochemical, molecular, and histopathological investigations. Results: The results showed that UPLE contains promising secondary metabolites that considerably lessen the negative effects of Cd on liver. Furthermore, UPLE inhibited oxidative stress and inflammation; restored antioxidant molecules; and promoted nuclear-related factor-2 (Nrf-2) expression. Also, UPLE improved the histopathological alterations induced by Cd. Discussion: This study explored the beneficial role of UPLE treatment in Cd-induced liver injury through enhancing Nrf-2 signaling and antioxidant enzyme gene expression in the liver of mice. Therefore, UPLE could have valuable implications against hepatotoxicity induced by environmental cadmium exposure. Which can be used as a chelating agent against Cd.

19.
Indian J Biochem Biophys ; 50(3): 186-95, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23898481

RESUMO

A phospholipase A2 belonging to IIA group secretory PLA2 was isolated and purified to homogeneity from the intestine of common stingray (Dasyatis pastinaca) using acidic treatment (pH 1.5) and ammonium sulphate precipitation methods combined with single-column ion-exchange chromatography. The purified enzyme was found to be a glycosylated monomeric protein with a molecular mass of about 14 kDa. The stingray sPLA2-IIA had optimum activity at 45 degrees C, unlike known mammalian PLA2-IIAs, which show optimum activity at 37 degrees C. The purified enzyme exhibited a specific activity of 290 U/mg at optimal conditions (pH 9.5 and 45 degrees C) in the presence of 6 mM NaDC and 8 mM CaCl2 with egg yolk as substrate. The NH2-terminal sequence of the enzyme and some protein fragments obtained from its tryptic digestion were also determined. All sequences obtained were similar to those of sPLA2-IIA. The enzyme also showed good stability in the presence of organic solvents, acidic and alkaline pH media and high temperature conditions. Thus, the purified enzyme exhibited a number of unique and promising properties, making it a potential possible candidate for future applications in the treatment of phospholipid-rich industrial effluents and synthesis of useful preparations for the food production and processing industry.


Assuntos
Elasmobrânquios/metabolismo , Fosfolipases A2 do Grupo II/química , Fosfolipases A2 do Grupo II/isolamento & purificação , Intestinos/enzimologia , Animais , Ativação Enzimática , Estabilidade Enzimática , Especificidade por Substrato
20.
PeerJ ; 11: e15488, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37334116

RESUMO

Background: Males are more likely to develop autism as a neurodevelopmental disorder than females are, although the mechanisms underlying male vulnerability are not fully understood. Therefore, studying the role of autism etiologies considering sex differences in the propionic acid (PPA) rodent model of autism would build greater understanding of how females are protected from autism spectrum disorder, which may be used as a treatment strategy for males with autism. Objectives: This study aimed to investigate the sex differences in oxidative stress, glutamate excitotoxicity, neuroinflammation, and gut microbiota impairment as etiological mechanisms for many neurological diseases, with specific reference to autism. Method: Forty albino mice were divided into four groups of 10 animals each with two control and two treated groups of both sexes received only phosphate-buffered saline or a neurotoxic dose of PPA (250 mg/kg body weight) for 3 days, respectively. Biochemical markers of energy metabolism, oxidative stress, neuroinflammation, and excitotoxicity were measured in mouse brain homogenates, whereas the presence of pathogenic bacteria was assessed in mouse stool samples. Furthermore, the repetitive behavior, cognitive ability, and physical-neural coordination of the animals were examined. Results: Collectively, selected variables related to oxidative stress, glutamate excitotoxicity, neuroinflammation, and gut bacteria were impaired concomitantly with altered behavior in PPA-induced rodent model, with males being more susceptible than females. Conclusion: This study explains the role of sex in the higher vulnerability of males to develop autistic biochemical and behavioral features compared with females. Female sex hormones and the higher detoxification capacity and higher glycolytic flux in females serve as neuroprotective contributors in a rodent model of autism.


Assuntos
Transtorno do Espectro Autista , Feminino , Animais , Masculino , Camundongos , Transtorno do Espectro Autista/induzido quimicamente , Roedores/metabolismo , Caracteres Sexuais , Doenças Neuroinflamatórias , Ácido Glutâmico/metabolismo
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